Centrifugal machine



Filed July 9, 1952 Plain lNvENToR 'Fl ETE-R VAN RIEL.

' AGENTS Patented Apr. 27, 1954 CENTRIFUGAL MACHINE Pieter van Riel,Delft, Netherlands, assignor to Machinefabriek Reinevcld N. V., Delft,Netherlands, a company Application July 9, 1952, Serial No. 297,923

Claims priority, application Netherlands July 20, 1951 3 Claims.

The invention relates to a centrifugal machine having a conicaldiverging perforated inner drum and a distributing drum located thereinand adapted to rotate with an angular speed slightly differing from thatof the inner drum and having blades or flights at its outer surfaceextending along substantially the whole length of the surface of thedrum. Continuously operating centrifugal machines of this kind are usedfor dewatering granular materials, such as fine grained coal,crystallized substances and the like. mass on the narrow part of theperforated screen drum indeed rapidly loses its water, but on the largerdiameter end of the drum the mass under treatment is practically notfurther dewatered. As, however, the frictional resistance of the gran-'ular material is materially increased due to the loss of water theparticles of the material on the last part of the drum are crushed.

The invention has for its object to improve the treatment of thematerial in a centrifugal ma chine of the kind referred to and to thisend additional blades are provided on the distributing drum at its largediameter end between the main blades, said additional blades extendingalong about half the axial length of the drum and said main bladeshaving a passage opposite the end of the additional blades. Through saidpassage The part of the mass moving along a main blade passes to theadjacent additional blade so that on the large diameter portion of thedrum the mass is distributed over double the number of blades andconsequently on a larger surface.

Thereby it .will be possible to supply a larger quantity of material tothe centrifugal machine so that its capacity is increased withoutreducing the rate of dewatering of the material, whereas crushing of thematerial due to increased frictional resistance is prevented.

In the drawing Fig. 1 shows a diagrammatical sectional elevation of acentrifugal machine provided with a distributing drum according to theinvention;

Fig.2 is a view of the curved surface of the distributing drum indeveloped condition.

The screen drum l is secured to a hollow shaft 2 enclosing the shaft 3of the distributing drum 4. The motor 5 drives the distributing drum 4through the intermediary of a toothed gear 6 and the screen drum Ithrough the intermediary of a gear 1. r

The distributing drum! is provided with main blades 8 which have apassage 9 about in the middle of their length. At the large diameter endof the drum an additional blade 19 is ar-.. ranged between each pair ofadjacent blades 8.

The passages 9 of adjacent main blades 8 are staggered with respectto'each other and the respective additional blades extend beyond thepassage of the adjacent main blade so that the additional blades havedifferent length. The passages 9 in the main blades have a fixedrelationship with respect to the adjacent end of the additional blades I0. The staggered arrangement of the passages 9 of the main blades 8prevents the material under treatment on one of the main blades fromreaching the adjacent main blade.

What I claim is:

'1. In a centrifugal machine comprising a conical screen drum and adistributing drum posi tioned to rotate inside said screen drum andhaving a number of main blades at its outer surface extendingsubstantially along the whole axial length of the drum, the provision ofadditional blades between adjacent main blades at the large diameter endof the drum and extending along about half the axial length of the drumand each of said main blades having a passage therethrough facing theend of the adjacent additional blades remote from the large diameter endof the drum.

2. A centrifugal machine as claimed in claim 1, wherein the passages inadjacent main blades are staggered with respect to each other.

3. In a centrifugal machine comprising a conical screen drum and adistributing drum positioned to rotate inside said screen drum in spacedrelationship therewith, a first, a second and a third series of bladesmounted on the outside of said distributing drum to extend substantiallyacross the space between said drums, the blades of said first seriesextending substantially axially of said distributing drum from the largediameter end thereof up to a first point substantially half way betweenthe ends thereof, the blades of second series being each alined with ablade of said first series and extending froma second point slightlyspaced from said first point up to the small diameter end of saiddistributing drum, and the blades of said third series alternating withthe blades of said first series and extending from said large diameterend and across the space defined between said first and second pointsand terminating short of said small diameter end, thereby to provide alarger number of blades at said large diameter end than at said smalldiameter end.

References'Cited in the file Ofthis patent UNITED STATES PATENTS NumberName 7 Date 905,860 Ericsson Dec. 8,1908 1,235,193 Elmore July 31, 19172,249,306 Bailly July 15, 1941

